Method and system for interest encryption in a content centric network

ABSTRACT

One embodiment provides a system that facilitates efficient content exchange in a CCN. During operation, the system receives, generates, by a client computing device, an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the name is a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level. The system computes a key based on a second hash of the original name components and a randomly generated first nonce. The system encrypts a payload of the interest with the key, wherein the interest indicates the first nonce. In response to transmitting the interest, wherein the interest allows a receiving content producing device to compute the key and decrypt the payload, the system receives receiving a content object with a payload encrypted based on the key.

RELATED APPLICATIONS

The subject matter of this application is related to the subject matter in the following applications:

-   -   U.S. patent application Ser. No. 13/847,814 (Attorney Docket No.         PARC-20120537-US-NP), entitled “ORDERED-ELEMENT NAMING FOR         NAME-BASED PACKET FORWARDING,” by inventor Ignacio Solis, filed         20 Mar. 2013 (hereinafter “U.S. patent application Ser. No.         13/847,814”);     -   U.S. patent application Ser. No. 12/338,175 (Attorney Docket No.         PARC-20080626-US-NP), entitled “CONTROLLING THE SPREAD OF         INTERESTS AND CONTENT IN A CONTENT CENTRIC NETWORK,” by         inventors Van L. Jacobson and Diana K. Smetters, filed 18 Dec.         2008 (hereinafter “U.S. patent application Ser. No.         12/338,175”); and     -   U.S. patent application Ser. No. 14/947,810 (Attorney Docket No.         PARC-20150245US01), entitled “TRANSPARENT ENCRYPTION IN A         CONTENT CENTRIC NETWORK,” by inventor Christopher A. Wood, filed         20 Nov. 2015 (hereinafter “U.S. patent application Ser. No.         14/947,810”);         the disclosures of which are herein incorporated by reference in         their entirety.

BACKGROUND

Field

This disclosure is generally related to distribution of digital content. More specifically, this disclosure is related to a system for interest encryption which facilitates efficient content exchange between a consumer and a producer in a content centric network.

Related Art

The proliferation of the Internet and e-commerce continues to create a vast amount of digital content. Content centric network (CCN) architectures have been designed to facilitate accessing and processing such digital content. A CCN includes entities, or nodes, such as network clients, forwarders (e.g., routers), and content producers, which communicate with each other by sending interest packets for various content items and receiving content object packets in return. CCN interests and content objects are identified by their unique names, which are typically hierarchically structured variable length identifiers (HSVLI). An HSVLI can include contiguous name components ordered from a most general level to a most specific level.

A client or consumer retrieves content from a CCN by issuing an interest with a unique name to the network. A CCN interest may also carry an optional payload to “push” information to a producer. To protect any sensitive information in the interest, current techniques allow the consumer to either establish a secret key with the producer to encrypt the private data or use the producer's public key to encrypt the private data. In the former case, the consumer and producer must exchange information using a key exchange protocol in establish a shared secret key. In the latter case, the consumer must already possess the producer's public key or perform an information exchange over the network to retrieve the producer's public key. These techniques require more than one round trip time (“RTT”) interest-content exchange or a priori knowledge of a target producer's public key, which can affect the efficiency of content distribution in a CCN.

SUMMARY

One embodiment provides a system that facilitates efficient content exchange in a CCN. During operation, the system receives, generates, by a client computing device, an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the name is a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level. The system computes a key based on a second hash of the original name components and a randomly generated first nonce. The system encrypts a payload of the interest with the key, wherein the interest indicates the first nonce. In response to transmitting the interest, wherein the interest allows a receiving content producing device to compute the key and decrypt the payload, the system receives receiving a content object with a payload encrypted based on the key, thereby reducing delay in interest encryption in a content centric network.

In some embodiments, the system determines a first value based on a first Diffie-Hellman parameter and a randomly generated second nonce. The system determines a second value based on the second hash, wherein the second hash is further based on a second Diffie-Hellman parameter. The system computes the key based on the first value and the second value, wherein the interest further indicates the first value and the second parameter.

In some embodiments, the system appends the first value, the first nonce, and the second parameter to the name for the interest.

In some embodiments, computing the key is further based on a key derivation function performed on the first value and the second value.

In some embodiments, the content object indicates configuration information to be used in subsequent communication between the client computing device and the content producing device, and the configuration information is indicated as one or more of: embedded in the content object; and included as a link in the content object.

In some embodiments, in response to receiving the content object, the system decrypts the payload based on the key.

In some embodiments, encrypting the payload with the key is based on an authenticated encryption with associated data algorithm which outputs an authenticator tag, and the interest further indicates the authenticator tag.

In another embodiment of the present invention, the system receives, by a content producing device, an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the name is a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level, wherein the interest indicates a first nonce, and wherein a payload of the interest is encrypted based on a key. The system computes the key based on a second hash of the original name components and the first nonce. The system decrypts a payload of the interest based on the key, and generates a content object with a payload encrypted based on the key, thereby reducing delay in interest encryption in a content centric network.

In a variation on this embodiment, the interest further indicates a first value and a first Diffie-Hellman parameter, and computing the key further involves: determining a second value based on the second hash, wherein the second hash is further based on the first parameter; and computing the key based on a key derivation function performed on the first value and the second value.

In some embodiments, the name for the interest includes the first value, the first nonce, and the first parameter.

In some embodiments, the system obtains the original name components based on a previously stored mapping of the first hash to the original name components.

In some embodiments, the system indicates in the content object configuration information to be used in subsequent communication between the client computing device and the content producing device, wherein indicating the configuration information further involves one or more of: embedding in the content object the configuration information; and including in the content object a link to the configuration information.

In some embodiments, the payload is further encrypted based on an encryption with associated data algorithm which outputs an authenticator tag, wherein the interest further indicates the authenticator tag, and wherein decrypting the payload involves: verifying the authenticator tag.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates an exemplary environment which facilitates efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 2A illustrates exemplary interests and content objects for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 2B illustrates an exemplary interest and content object for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 2C illustrates an exemplary interest and content object for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 2D illustrates an exemplary interest and content object for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 3 presents a flow chart illustrating a method by a client computing device for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 4 presents a flow chart illustrating a method by a content producing device for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 5A illustrates an exemplary computer system that facilitates efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

FIG. 5B illustrates an exemplary computer system that facilitates efficient content exchange in a content centric network, in accordance with an embodiment of the present invention.

In the figures, like reference numerals refer to the same figure elements.

DETAILED DESCRIPTION

The following description is presented to enable any person skilled in the art to make and use the embodiments, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. Thus, the present invention is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

Overview

Embodiments of the present invention provide a system for efficient content exchange which obviates the traditional round trip time (“RTT”) required for a consumer to obtain a producer's key and encrypt an interest destined for the producer. Current techniques for protecting sensitive information in an interest require the consumer to already possess the producer's public key or to perform at least one round trip interest-content object exchange to obtain the producer's public key or to establish a shared secret key. Embodiments of the present invention eliminate these requirements by providing a protocol which allows a consumer to encrypt the payload of an interest and provide information in the interest which allows only the producer to compute the key and subsequently decrypt the encrypted payload of the interest. This protocol is a stateless interest encryption and is based on the Diffie-Hellman algorithm.

Assume that a name for an interest includes a routable prefix and one or more original name components (“N”). The consumer computes a secret key (“k”) based on the original name components N and additional variables, including standard Diffie-Hellman parameters and randomly generated nonces. The consumer encrypts the interest payload with the secret key k and includes as cleartext in the interest some of the additional variables used to compute k. The variables may be included in the interest name or in a field or fields of the interest. The consumer also includes in the interest name a hash of some of the original name components (e.g., “h(N)”). A transparent encryption protocol that masks both the name and the content is described in U.S. patent application Ser. No. 14/947,810, which disclosure is herein incorporated by reference in its entirety.

When the producer publishes the content corresponding to N, the producer stores a mapping between N and h(N). Upon receiving the interest with the name that includes h(N), the producer can easily extract or obtain N. The producer can then compute the secret key k using its knowledge of N and the additional variables included in the interest. The producer can decrypt the interest payload and encrypt a responsive content object payload using k. Only an entity with knowledge of the mapping between N and h(N) can use the cleartext variables included in the interest to compute the secret key k. That is, the cleartext variables alone cannot be used by a malicious node to compute the secret key. The protocol is described below in relation to FIG. 1.

In addition, the producer may choose to include in the responsive content object configuration information that includes, e.g., the producer's public key, which the consumer can use in subsequent communications with the producer. The producer can include the configuration information by embedding it in the content object or by including a link to it in the content object, as described below in relation to FIGS. 2C and 2D.

Thus, the system provides a secure and efficient method for content exchange between a consumer and a producer that eliminates the need to first establish a shared state (i.e., a RTT interest-content object exchange to determine a shared secret key).

In CCN, each piece of content is individually named, and each piece of data is bound to a unique name that distinguishes the data from any other piece of data, such as other versions of the same data or data from other sources. This unique name allows a network device to request the data by disseminating a request or an interest that indicates the unique name, and can obtain the data independent from the data's storage location, network location, application, and means of transportation. The following terms are used to describe the CCN architecture:

Content Object (or “content object”): A single piece of named data, which is bound to a unique name. Content Objects are “persistent,” which means that a Content Object can move around within a computing device, or across different computing devices, but does not change. If any component of the Content Object changes, the entity that made the change creates a new Content Object that includes the updated content, and binds the new Content Object to a new unique name.

Unique Names: A name in a CCN is typically location independent and uniquely identifies a Content Object. A data-forwarding device can use the name or name prefix to forward a packet toward a network node that generates or stores the Content Object, regardless of a network address or physical location for the Content Object. In some embodiments, the name may be a hierarchically structured variable-length identifier (HSVLI). The HSVLI can be divided into several hierarchical components, which can be structured in various ways. For example, the individual name components parc, home, ccn, and test.txt can be structured in a left-oriented prefix-major fashion to form the name “/parc/home/ccn/test.txt.” Thus, the name “/parc/home/ccn” can be a “parent” or “prefix” of “/parc/home/ccn/test.txt.” Additional components can be used to distinguish between different versions of the content item, such as a collaborative document.

In some embodiments, the name can include an identifier, such as a hash value that is derived from the Content Object's data (e.g., a checksum value) and/or from elements of the Content Object's name. A description of a hash-based name is described in U.S. patent application Ser. No. 13/847,814, which is herein incorporated by reference. A name can also be a flat label. Hereinafter, “name” is used to refer to any name for a piece of data in a name-data network, such as a hierarchical name or name prefix, a flat name, a fixed-length name, an arbitrary-length name, or a label (e.g., a Multiprotocol Label Switching (MPLS) label).

Interest (or “interest”): A packet that indicates a request for a piece of data, and includes a name (or a name prefix) for the piece of data. A data consumer can disseminate a request or Interest across an information-centric network, which CCN/NDN routers can propagate toward a storage device (e.g., a cache server) or a data producer that can provide the requested data to satisfy the request or Interest.

The methods disclosed herein are not limited to CCN networks and are applicable to other architectures as well. A description of a CCN architecture is described in U.S. patent application Ser. No. 12/338,175, which is herein incorporated by reference.

Exemplary Network and Communication

FIG. 1 illustrates an exemplary environment which facilitates efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. A network 100 can include a consumer or content requesting device 116, producers or content producing devices 118 and 120, and a router or other forwarding device at nodes 102, 104, 106, 108, 110, 112, and 114. A node can be a computer system, an end-point representing users, and/or a device that can generate interests or originate content. A node can also be an edge router (e.g., CCN nodes 102, 104, 112, and 114) or a core router (e.g., intermediate CCN routers 106, 108, and 110). Network 100 can be a content centric network.

During operation, client computing device 116 can generate an interest 150 with a name 150.1 of “/r_prefix/N.” Assume that a name for an interest includes a routable prefix (e.g., “r_prefix”) which is not encrypted so that the interest can be routed to the appropriate producer. Assume that the name also includes one or more name components (e.g., “N”). Additionally, assume the following: “p” and “g” are standard DF algorithm parameters; “H_(p)(•)” is a hash function that maps its input to integers modulo p; “h(•)” is a standard cryptographic function used to identify the content with the name N; and “KDF” is a key derivation function.

Client computing device 116 can compute the secret key “k” as follows (function 170): Device 116 can generate two random numbers, “r₁ modulo p” and “r₂ modulo p.” Device 116 can compute two values, “x” and “y,” such that:

x=g ^(r1)  Equation (1)

y=H _(p)(N∥r ₂)  Equation (2)

Device 116 can then compute a value “s” from which the key k is derived:

s=x ^(y) modulo p  Equation (3)

k=KDF(s)  Equation (4)

In some embodiments, device 116 uses a standard Authenticated Encryption with Associated Data (AEAD) algorithm (e.g., AES-GCM or AES-CWC), which outputs an authenticator tag “t.” Device 116 can save the authenticator tag t.

Device 116 can replace N with h(N) in name 150.1 for interest 150 (as depicted in an interest 152 with a name 152.1). Device 116 can also include x, r₂, p, and t in interest 152, either by appending these values to the interest name or including them in special fields of the interest. Device 116 can encrypt a payload 152.2 of interest 152 with the key k (function 172). For example, interest 152 can have a name 152.1 with a value of “/r_prefix/(h(N), x, r₂, p, t)” where N is equal to, e.g., “/a/b/c,” and a payload 152.2 with “<data>” encrypted based on the key k. Device 116 can transmit interest 152 destined for content producing device 118. Interest 152 can travel through network 100 via nodes or routers 102, 110, and 112, finally reaching content producing device or producer 118.

Upon receiving interest 152, content producing device 118 can extract h(N), x, r₂, p, and t. Device 118 can obtain N from h(1V) based on a previous mapping and having already computed the image of N before publishing the corresponding content. Device 118 can generate a responsive content object 160 with a name 160.1 of “/r_prefix/N,” and compute the key kin similar fashion as the consumer (function 180). For example, device 118 can compute y=H_(p) (N∥r₂) (Equation (2)) and s=x^(y) modulo p (Equation (3)), and can recover the key k by computing k=KDF(s) (Equation (4)). Device 118 can subsequently decrypt the payload of interest using the key k (function 180). Device 118 can further verify the authenticator tag t, if included. Device 118 can also encrypt a payload of a responsive content object 162 with a name 162.1 of “/r_prefix/(h(N), x, r₂, p, t)” and a payload 162.2 with “<data>” encrypted based on the key k (function 184).

In some embodiments, the consumer (e.g., client computing device 116) and the producer (e.g., content producing device 118) can derive the shared key k from a suitable KDF function using “h(N∥r)” as the input, where “r” is a random nonce with sufficient entropy:

k=KDF(h(N∥r))  Equation (5)

The producer can then generate a responsive content object with a payload encrypted based on the key k.

Note that in FIG. 1, the interest packet generated and transmitted by device 116 is depicted as two interests (150 and 152) for the sake of illustration. Similarly, the responsive content object created and transmitted by device 118 is depicted as two content objects (160 and 162) for the sake of illustration.

Exemplary Interests and Content Objects

FIG. 2A illustrates exemplary interests 150 and 151 and content objects 160 and 161 for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. As mentioned above, for the sake of illustration, interests 150 and 152 are depicted as two interests, while content objects 160 and 162 are depicted as two content objects. Interest 150 can have a name 150.1 of “/r_prefix/N” and interest 152 can have a name 152.1 of “/r_prefix/(h(N), x, r₂, p, t)” and a payload 152.2 with “<data>” encrypted based on the key k. Content object 160 can have a name 160.1 of “/r_prefix/N” and content object 162 can have a name 162.1 of “/r_prefix/(h(N), x, r₂, p, t)” and a payload 162.2 with “<data>” encrypted based on the key k. Interest 152 and content object 162 correspond, respectively, to CCN packets 152 and 162 exchanged between client computing device 116 and content producing device 118 of FIG. 1.

FIG. 2B illustrates an exemplary interest 151 and content object 161 for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. Interest 151 is similar to interest 152 of FIG. 2A, with the difference that interest 151 does not include the authenticator tag t outputted by an AEAD algorithm (e.g., as shown in a name 151.1 with a value of “/r_prefix/(h(N), x, r₂, p)”). Correspondingly, content object 161 is similar to content object 162 of FIG. 2A, with the difference that content object 161 does not include the authenticator tag t outputted by an AEAD algorithm (e.g., as shown in a name 161.1 with a value of “/r_prefix/(h(N), x, r₂, p)”).

FIG. 2C illustrates an exemplary interest 152 and content object 164 for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. Interest 152 corresponds to interest 152 of FIG. 2A. Content object 164 is similar to content object 162 of FIG. 2A, with the difference that a payload 164.2 for content object 164 includes configuration information (e.g., “config_file”) embedded in content object 164.

FIG. 2D illustrates an exemplary interest 152 and content object 166 for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. Interest 152 corresponds to interest 152 of FIG. 2A. Content object 166 is similar to content object 162 of FIG. 2A, with the difference that a payload 166.2 for content object 166 includes configuration information (e.g., “*config_file”) included as a link in content object 166.

Role of Client Computing Device in Generating Encrypted Interest

FIG. 3 presents a flow chart 300 illustrating a method by a client computing device for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. During operation, the system generates, by a client computing device, an interest with a name that includes a routable prefix and one or more original name components (“N”) (operation 302). The interest name can be a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level. The system computes a secret key (“k”) based on a randomly generated first nonce (“r₂”), the original name components N, and additional variables (operation 304). The additional variables can include standard Diffie-Hellman parameters (“p” and “g”), randomly generated nonces (“r₁” and “r₂”), and other variables (e.g., “x,” “y,” and “s”), as described above in relation to FIG. 1.

The system replaces the original name components N in the name for the interest with a cryptographic hash of the original name components (“h(N)”), where the interest indicates the first nonce r₂ and the additional variables (operation 306). For example, the name can be “/r_prefix/(h(N), x, r₂, p)” where x, r₂, p, and other additional variables (such as the authenticator tag “t”) can be included as cleartext in the interest name. These variables can also be included in a special field or fields of the interest. The system encrypts the payload of the interest with the key k (operation 308). In response to transmitting the interest, the system receives a content object with a payload encrypted based on the key k (operation 310). The transmitted encrypted interest allows a receiving content producing device to compute the key k, decrypt the payload of the interest with the key k, and encrypt the payload of the responsive content object with the key k. In addition, the responsive content object can indicate configuration information (e.g., the public key of the content producing device) to be used in subsequent communications between the client computing device and the content producing device.

Role of Content Producing Device in Returning Responsive Content Object

FIG. 4 presents a flow chart 400 illustrating a method by a content producing device for facilitating efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. During operation, the system receives, by a content producing device, an interest with a name that includes a routable prefix and a hash of one or more original name components (“h(N)”), wherein the interest indicates a first nonce (“r₂”) and additional variables, and wherein a payload of the interest is encrypted based on a key (“k”) (operation 402). The system obtains the original name components N based on a previously stored mapping of h(N) to N (operation 404). The system computes the key k based on the original name components N, the first nonce r₂, and the additional variables (operation 406). The system then decrypts the payload of the interest with the key k (operation 408). The system generates a responsive content object with a payload encrypted based on the key k (operation 410). The system can optionally include in the content object a configuration file embedded in the content object or as a link in the content object (operation 412, depicted with dashed lines).

Exemplary Computer Systems

FIG. 5A illustrates an exemplary computer system 502 that facilitates efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. Computer system 502 includes a processor 504, a memory 506, and a storage device 508. Memory 506 can include a volatile memory (e.g., RAM) that serves as a managed memory, and can be used to store one or more memory pools. Furthermore, computer system 502 can be coupled to a display device 510, a keyboard 512, and a pointing device 514. Storage device 508 can store an operating system 516, a content-processing system 518, and data 530.

Content-processing system 518 can include instructions, which when executed by computer system 502, can cause computer system 502 to perform methods and/or processes described in this disclosure. Specifically, content-processing system 518 may include instructions for sending and/or receiving data packets to/from other network nodes across a computer network, such as a content centric network (communication module 520). A data packet can include an interest packet or a content object packet with a name which includes a routable prefix and a hash of one or more original name components.

Further, content-processing system 518 can include instructions for generating an interest with a name that includes a routable prefix and a first hash of one or more original name components (packet-generating module 522). Content-processing system 518 can include instructions for computing a key based on a second hash of the original name components and a randomly generated first nonce (key-computing module 524). Content-processing system 518 can also include instructions for encrypting a payload of the interest with the key, wherein the interest indicates the first nonce (packet-encrypting module 526). Content-processing system 518 can include instructions for, in response to transmitting the interest, receiving a content object with a payload encrypted based on the key (communication module 520).

Content-processing system 518 can additionally include instructions for: determining a first value based on a first standard Diffie-Hellman algorithm parameter and a randomly generated second nonce; determining a second value based on the second hash, wherein the second hash is further based on a second standard Diffie-Hellman algorithm parameter; and computing the key based on the first value and the second value (key-computing module 524). Content-processing system 518 can include instructions for appending the first value, the first nonce, and the second parameter to the name for the interest (packet-generating module 522). Content-processing system 518 can include instructions for, in response to receiving the content object (communication module 520), decrypting the payload based on the key (packet-decrypting module 528).

FIG. 5B illustrates an exemplary computer system 552 that facilitates efficient content exchange in a content centric network, in accordance with an embodiment of the present invention. Computer system 552 includes a processor 554, a memory 556, and a storage device 558. Memory 556 can include a volatile memory (e.g., RAM) that serves as a managed memory, and can be used to store one or more memory pools. Furthermore, computer system 552 can be coupled to a display device 560, a keyboard 562, and a pointing device 564. Storage device 558 can store an operating system 566, a content-processing system 568, and data 580.

Content-processing system 568 can include instructions, which when executed by computer system 552, can cause computer system 552 to perform methods and/or processes described in this disclosure. Specifically, content-processing system 568 may include instructions for sending and/or receiving data packets to/from other network nodes across a computer network, such as a content centric network (communication module 570). A data packet can include an interest packet or a content object packet with a name which includes a routable prefix and a hash of one or more original name components.

Furthermore, content-processing system 568 can include instructions for receiving an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the interest indicates a first nonce, and wherein a payload of the interest is encrypted based on a key (communication module 570). Content-processing system 568 can include instructions for computing the key based on a second hash of the original name components and a randomly generated first nonce (key-computing module 574). Content-processing system 568 can also include instructions for decrypting a payload of the interest based on the key (packet-decrypting module 578), and for generating a content object with a payload encrypted based on the key (packet-generating module 572 and packet-encrypting module 576). Content-processing system 568 can include instructions for verifying an authenticator tag (packet-decrypting module 578).

Content-processing system 568 can additionally include instructions for: determining a second value based on the second hash, wherein the second hash is further based on the first parameter; and computing the key based on a key derivation function performed on a first value indicated in the interest and the second value (key-computing module 574). Content-processing system 568 can include instructions for obtaining the original name components based on a previously stored mapping of the first hash to the original name components (key-computing module 574).

Content-processing system 568 can also include instructions for indicating in the content object configuration information to be used in subsequent communications between the client computing device and the content producing device, wherein indicating the configuration information further involves one or more of: embedding in the content object the configuration information; and including in the content object a link to the configuration information (packet-generating module 572).

Data 530 and data 580 can include any data that is required as input or that is generated as output by the methods and/or processes described in this disclosure. Specifically, data 530 and data 580 can store at least: an interest or a content object packet; a name; a name that is an HSVLI; a routable prefix; one or more original name components; a first hash of one or more original name components; a randomly generated first nonce; a randomly generated second nonce; a second hash of the original name components and the first nonce; a payload; a key; a payload of an interest or a content object encrypted based on the key; a first standard Diffie-Hellman algorithm parameter; a second standard Diffie-Hellman algorithm parameter; a first value based on the first Diffie-Hellman parameter and the second nonce; a second value based on the second hash; a key derivation function; configuration information; configuration information embedded in a content object or included as a link in the content object; an authenticated encryption with associated data algorithm; an authenticator tag; and an interest or an interest name that indicates the first hash, the first value, the first nonce, and the first Diffie-Hellman parameter.

The data structures and code described in this detailed description are typically stored on a computer-readable storage medium, which may be any device or medium that can store code and/or data for use by a computer system. The computer-readable storage medium includes, but is not limited to, volatile memory, non-volatile memory, magnetic and optical storage devices such as disk drives, magnetic tape, CDs (compact discs), DVDs (digital versatile discs or digital video discs), or other media capable of storing computer-readable media now known or later developed.

The methods and processes described in the detailed description section can be embodied as code and/or data, which can be stored in a computer-readable storage medium as described above. When a computer system reads and executes the code and/or data stored on the computer-readable storage medium, the computer system performs the methods and processes embodied as data structures and code and stored within the computer-readable storage medium.

Furthermore, the methods and processes described above can be included in hardware modules. For example, the hardware modules can include, but are not limited to, application-specific integrated circuit (ASIC) chips, field-programmable gate arrays (FPGAs), and other programmable-logic devices now known or later developed. When the hardware modules are activated, the hardware modules perform the methods and processes included within the hardware modules.

The foregoing descriptions of embodiments of the present invention have been presented for purposes of illustration and description only. They are not intended to be exhaustive or to limit the present invention to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. Additionally, the above disclosure is not intended to limit the present invention. The scope of the present invention is defined by the appended claims. 

What is claimed is:
 1. A computer system for facilitating efficient content exchange, the system comprising: a processor; and a storage device storing instructions that when executed by the processor cause the processor to perform a method, the method comprising: generating, by a client computing device, an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the name is a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level; computing a key based on a second hash of the original name components and a randomly generated first nonce; encrypting a payload of the interest with the key, wherein the interest indicates the first nonce; in response to transmitting the interest, wherein the interest allows a receiving content producing device to compute the key and decrypt the payload, receiving a content object with a payload encrypted based on the key, thereby reducing delay in interest encryption in a content centric network.
 2. The computer system of claim 1, wherein computing the key further involves: determining a first value based on a first Diffie-Hellman parameter and a randomly generated second nonce; determining a second value based on the second hash, wherein the second hash is further based on a second Diffie-Hellman parameter; and computing the key based on the first value and the second value, wherein the interest further indicates the first value and the second parameter.
 3. The computer system of claim 2, wherein the method further comprises: appending the first value, the first nonce, and the second parameter to the name for the interest.
 4. The computer system of claim 2, wherein computing the key is further based on a key derivation function performed on the first value and the second value.
 5. The computer system of claim 1, wherein the content object indicates configuration information to be used in subsequent communication between the client computing device and the content producing device, wherein the configuration information is indicated as one or more of: embedded in the content object; and included as a link in the content object.
 6. The computer system of claim 1, wherein the method further comprises: in response to receiving the content object, decrypting the payload based on the key.
 7. The computer system of claim 1, wherein encrypting the payload with the key is based on an authenticated encryption with associated data algorithm which outputs an authenticator tag, and wherein the interest further indicates the authenticator tag.
 8. A computer system for facilitating efficient content exchange, the system comprising: a processor; and a storage device storing instructions that when executed by the processor cause the processor to perform a method, the method comprising: receiving, by a content producing device, an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the name is a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level, wherein the interest indicates a first nonce, and wherein a payload of the interest is encrypted based on a key; computing the key based on a second hash of the original name components and the first nonce; decrypting a payload of the interest based on the key; and generating a content object with a payload encrypted based on the key, thereby reducing delay in interest encryption in a content centric network.
 9. The computer system of claim 8, wherein the interest further indicates a first value and a first Diffie-Hellman parameter, and wherein computing the key further involves determining a second value based on the second hash, wherein the second hash is further based on the first parameter; and computing the key based on a key derivation function performed on the first value and the second value.
 10. The computer system of claim 9, wherein the name for the interest includes the first value, the first nonce, and the first parameter.
 11. The computer system of claim 8, wherein the method further comprises: obtaining the original name components based on a previously stored mapping of the first hash to the original name components.
 12. The computer system of claim 8, wherein the method further comprises: indicating in the content object configuration information to be used in subsequent communication between the client computing device and the content producing device, wherein indicating the configuration information further involves one or more of: embedding in the content object the configuration information; and including in the content object a link to the configuration information.
 13. The computer system of claim 8, wherein the payload is further encrypted based on an encryption with associated data algorithm which outputs an authenticator tag, wherein the interest further indicates the authenticator tag, and wherein decrypting the payload involves: verifying the authenticator tag.
 14. A computer-implemented method for facilitating efficient content exchange, the method comprising: generating, by a client computing device, an interest with a name that includes a routable prefix and a first hash of one or more original name components, wherein the name is a hierarchically structured variable length identifier that includes contiguous name components ordered from a most general level to a most specific level; computing a key based on a second hash of the original name components and a randomly generated first nonce; encrypting a payload of the interest with the key, wherein the interest indicates the first nonce; in response to transmitting the interest, wherein the interest allows a receiving content producing device to compute the key and decrypt the payload, receiving a content object with a payload encrypted based on the key, thereby reducing delay in interest encryption in a content centric network.
 15. The method of claim 14, wherein computing the key further involves: determining a first value based on a first Diffie-Hellman parameter and a randomly generated second nonce; determining a second value based on the second hash, wherein the second hash is further based on a second Diffie-Hellman parameter; and computing the key based on the first value and the second value, wherein the interest further indicates the first value and the second parameter.
 16. The method of claim 15, further comprising: appending the first value, the first nonce, and the second parameter to the name for the interest.
 17. The method of claim 15, wherein computing the key is further based on a key derivation function performed on the first value and the second value.
 18. The method of claim 14, wherein the content object indicates configuration information to be used in subsequent communication between the client computing device and the content producing device, wherein the configuration information is indicated as one or more of: embedded in the content object; and included as a link in the content object.
 19. The method of claim 14, further comprising: in response to receiving the content object, decrypting the payload based on the key.
 20. The method of claim 14, wherein encrypting the payload with the key is based on an authenticated encryption with associated data algorithm which outputs an authenticator tag, and wherein the interest further indicates the authenticator tag. 